Rubens Barrichello and Jenson Button gave Honda spirits a lift today, by posting the two fastest times at Jerez. Weather conditions remained hot and sunny although the strong breeze from the previous day disappeared for much of the day.

The Japanese team, which has had a torrid time of late, focussed on set-ups, electrics and tyre evaluations, completing almost 180 laps.

The Brazilian began his day with a couple of familiarisation runs to acclimatise himself to the car and circuit. He then worked through a controls programme before finishing the morning session with a series of qualifying simulation runs. He then spent the afternoon evaluating the Hockenheim tyre options, using the best of the tyres from Button’s evaluation in the morning.

THe Englishman had a good morning session evaluating the tyres for the German Grand Prix and set some encouraging lap times. In the afternoon he worked through an aero programme.

Renault continued its programme, with Heikki Kovalainen and Jose Maria Lopez in action for the French team.

As this is the final test before the August testing ban, Kovalainen continued with an intensive tyre development programme in order to make selections for Germany, Hungary and Turkey by the end of the week.

Jose Maria Lopez continued running in low downforce configuration in order to accumulate mileage on these components. The Argentine has now completed his testing for the week, and will be replaced tomorrow by Fernando Alonso, who will also focus on tyre development with Michelin.

"We had a mixed day in Jerez," admitted Christian Silk, "with Heikki completing his entire programme - and Jose experiencing a number of problems. Heikki did a lot of tyre work, signing off selections for the next races, and completed his planned programme. Jose's car suffered from a number of problems during the day, and he completed fewer than 50 laps. However, in those he was able to achieve the primary objectives for the day, and will hand over to Fernando tomorrow."

Kovalainen was one of several drivers to bring out the red flag today, the Finn stopping on track following a mechanical problem. Barrichello and Heidfeld were the other 'culprits'.

BMW had Nick Heidfeld and Robert Kubica on duty. The German started in the morning with set-up and aero work and then tested different tyre compounds for next week's grand prix. In the afternoon he continued with set-up work and also did test work on brakes.

Kubica tested a new front wing in the morning and then switched to an evaluation programme with different tyre compounds for the Turkish Grand Prix, which takes place at the end of August. In the afternoon the Pole carried out a tyre testing programme for Michelin.

Jacques Villeneuve will join Kubica for the final day of testing on Friday.

Having dominated the first two days of testing, Pedro de la Rosa was a little further down the timesheets today, finishing eleventh quickest, his programme ending prematurely following a technical failure.

Work for both McLaren drivers centred on the tyre selection process for Germany and Hungary. In addition the Woking duo continued the work of the past two days on aero and mechanical developments to the MP4-21, with regular set-up changes during the course of the session requiring time spent in the garage between multiple short runs.

Gary Paffett will replace Pedro for the final day of testing.

Toyota had Olivier Panis and Ricardo Zonta on duty, however, the Brazilian's day lasted just one lap, his engine 'exploding' as he left the pits and causing serious fire damage to his car.

"Unfortunately I could not even get any work done today because I had an engine problem on my first lap of the day," said the Brazilian, in a masterpiece of understatement. "I went out for the first time after doing an installation lap and noticed that the engine was feeling strange. I stopped the car after seeing some smoke and it turned out that the car would have to be worked on the rest of the day. Olivier did a good job taking over my long runs as I could not complete them."

"This was a long strenuous day for me," admitted Panis, "having put in over 100 laps in these extreme temperatures. The heat does not make it any easier for you when you are sitting in the car for such a long time. Nevertheless, we managed to get through most of my and Ricardo's program. I did four long runs testing tyre compounds. The car was running like a strong truck just pushing through the programme today. I am really happy with the results and feel the test team did a good job considering the workload."